Thermal conductivity and dielectric properties of high thermal conductive adhesives in the large generator insulation materials

It had been researched the thermal conductivity and dielectric properties of high thermal conductive (HTC) main insulation for the large and medium generator stator bars. The thermal conductivity was analyzed by orthogonal test for the adhesive composed of BN powders and Tung-maleic-anhydride epoxy resin, and the BN with different particle sizes were used in the adhesive. It analyzed the variation of thermal conductivity for the adhesive composite with different BN powder contents, and the best thermal conductivity in the adhesives was 2.27 W/(m K). The variation of the dielectric properties was analyzed for the HTC adhesive by frequency-domain spectrum. It was detected by scanning electron microscope for the dispersion of the BN particles in TAEP and the bond state between the BN particles. The results indicated that the thermal conductivity of the best adhesives was increased by 13 times, and the other properties were almost the same as that of TAEP. Therefore, the HTC adhesive could be used in the main insulation of the large generator stator bars.